【正文】 C中所傳遞的荷載， 因?yàn)镚ESC中給柱子包裹土工合成材料使其強(qiáng)度和剛度變得更大?？捎蓤D 8中畫出的 CSC和 GESC在沉降量為 25mm時(shí)曲線， 看出對(duì)柱子包裹合成材料之后對(duì)端部承載力的影響和何在傳遞機(jī)制。因?yàn)橄鄬?duì)位移不同，它會(huì)嚴(yán)重影響表面摩擦力沿著柱子的分布形態(tài)，總的表 面摩擦力大小也將沿著柱子產(chǎn)生變化 （圖 7）。 另一方面， 在 GESCs中 ， 軟土地基與土工合成材料之間的相對(duì)沉降量不僅沿著整個(gè)柱子長度增大而增大，而且在研究中發(fā)現(xiàn)其值遠(yuǎn)大于 CSC中的相對(duì)沉降量。 The distribution of vertical displacements along the length of the column (Fig. 4) can affect the relative vertical displacements between the soft soil and the column material in the case of CSCs and between the soft soil and the geosynthetic in the case of GESCs. For the CSC at a vertical settlement of 25 mm, it can be seen (Fig. 5) that the value of relative displacement between On the other hand, for GESCs, the value of relative displacement between the soft soil and the geosynthetic not only extended along the entire length of the column, but was also much greater than the relative displacements that were observed for the CSC. the soft soil and the column material bees negligible after a depth of m. Almost the same lateral stresses were observed versus depth for both the CSC and GESC (Fig. 6). Differences in the values of relative displacement can therefore have a significant effect on the shape of the skin friction distribution along the columns and the magnitude of the overall skin friction force that is mobilized (Fig. 7). 沿 柱子縱向 分布的垂直位移會(huì)影響 CSC中 軟土 地基 和 柱子材料的 相對(duì)垂直位移 ，以及 GESC中的相對(duì)垂直位移 （圖 4）。 舉一個(gè)例子說明 ， 豎向 位移等于 5毫米 時(shí) ， 可以看到其 發(fā)生的 在 5D的 深度 。 實(shí)際 上，在 CSC中觀察發(fā)現(xiàn)豎向 位移主要是因?yàn)?在荷載作用下柱的橫向 材料膨脹 而不是因承受壓力產(chǎn)生的豎向沉降 。在 CSC（圖 4a） 中 ， 一定深度以后其豎向位移可以忽略不計(jì) （小于 5毫米）。 FIG. 2. Displacement vs. stress FIG. 3. Lateral bulging vs. 應(yīng)力 位移曲線 depth at a vertical settlement of 50 mm 豎向沉降量為 50mm下的側(cè)向位移 Having found that the use of encasement can noticeably enhance the loadcarrying capacity of CSCs (Fig. 2), it is instructive to more prehensively study the loadtransfer mechanism of both CSCs and GESCs. Figs. 4a and 4b show contours of vertical displacement for both the CSC and GESC, respectively. In the CSC (Fig. 4a), vertical displacements are negligible (less than 5 mm) after a depth of 1D. This is caused by the lateral bulging failure mechanism of the CSC, which occurs in the top portion of the column. In fact, the vertical displacements that are observed in CSCs appear to be mostly due to lateral bulging of the column material rather than vertical settlements due to pression of the column material under load. However, in the GESC (Fig. 4b), vertical displacements are distributed all along the column. As an example, vertical displacements equal to 5 mm were observed to occur up to a depth of 5D. The constrained lateral bulging behavior of the GESC (Fig. 3) is the explanation for the distribution of vertical displacements along the GESC, and the resulting improved behavior of the column. 經(jīng)發(fā)現(xiàn)， 對(duì)傳統(tǒng)碎石樁進(jìn)行包裹合成材料可以顯著的提高其承載能力（圖 2），有利于更加全面的研究 CSC和 GESC的荷載傳遞機(jī)制 。 這是由于 在 GESC中，能更多轉(zhuǎn)移頂部荷載 （圖 2） ，隨后傳遞到更深的地基土壤中。對(duì)于 被土工合成材料包裹的碎石樁來說 ，最 大側(cè) 向位移值遠(yuǎn)小于的 傳統(tǒng)碎石樁 。 The lateral bulging of the GESC and CSC at a settlement of 50 mm is shown in Fig. 3. It is observed that in the CSC, lateral bulging occurs up to depth of m(), after which lateral bulging bees negligible. For the GESC, the maximum value of lateral displacement is much less than that for the CSC. However, after a depth of 1D, 附件 C：譯文 C8 the GESC experiences more lateral displacement than the CSC. This is attributed to mobilization of more load on top of the GESC (Fig. 2), and the subsequent transmission of greater loads to higher depths in the case of the GESC. This phenomenon is studied further and discussed in more detail in the following sections. 圖 3顯示了沉降量為 50mm時(shí)， 被土工合成材料包裹的碎石樁和傳統(tǒng)碎石樁的 橫向膨脹 量 。例 如， 當(dāng) 沉降 量為 25mm（一種常 用的適用性標(biāo)準(zhǔn) 值 ） 時(shí) ， 被土工合成材料包裹的碎石樁頂部的可變豎向應(yīng)力比傳統(tǒng)碎石樁大了 。 Fig. 2 shows the stressdisplacement response for both a GESC and CSC having the parameters listed in Table 1. From Fig. 2, it can be seen that after a very small vertical settlement the mobilized vertical stress on top of the encased column is always greater than the CSC and the difference increases with additional settlement. For example, at a settlement of 25 mm (a mon serviceability criteria), the mobilized vertical stress on top of the GESC is times greater than that of CSC. This ratio bees for a settlement of 50 mm. 圖 2分別 顯示了 GESC和 CSC應(yīng)力 位移反應(yīng)， 相應(yīng) 的參數(shù) 在 表 1中 列出 。 附件 C：譯文 C7 Table 1. Material Parameters 表一：材料參數(shù) 項(xiàng)目 模型 φ(deg) C (kPa) Ψ(deg.) E (Mpa) ν κ λ M e 碎石樁 莫爾 庫倫 40 1 0 60 松軟地基 改良的滑移粘土 土工合成材料 線彈性 600 NUMERICAL RESULTS 數(shù)值結(jié)果 In order to determine the stressdisplacement behavior on top of the geosynthetic encased stone column, soil nodal points corresponding to the top of the column were subjected to a series of vertical downward displacements. During these downward displacements, the average resultant stress on top of the column was recorded , allowing the stressdisplacement curve to be drawn accordingly. 為了確定在 被土工合成材料包裹的碎石樁頂部的應(yīng)力與位移之間的關(guān)系 ，土壤結(jié)點(diǎn) 與碎石樁頂部受到的豎向沉降相一致。 In order to pare the performance of the GESC with a conventional stone column (CSC), parallel analyses were also performed on a stone column without encasement. In this case, like interaction between the geosynthetic and soft soil, the coefficient of sliding friction between the stone column and the soft soil was selected to be . 為了比較 被土工合成材料包裹的碎石樁（ GESC） 與傳統(tǒng) 碎石樁（ CSC）的 性能差異 ， 常在裸露碎石樁上采用平行比較分析 。 土工合成材料和 碎石樁之間的 滑動(dòng)摩擦系數(shù)（ μ ）取為 （ μ=2/3tanφ ） （ 美國 聯(lián)邦公路管理局， 2020年），其中 φ 是 碎石樁 材料摩擦角。 Interface elements, characterized by two sets of parameters, were used to model interaction behavior between the geosynthetic and the stone column, and between t